no code implementations • 31 Dec 2020 • Abdelrahman Mohamed, Dimiter Vassilev
We show that a compact quaternionic contact manifold of dimension seven that satisfies a Lichnerowicz-type lower Ricci-type bound and has the $P$-function of any eigenfunction of the sub-Laplacian non-negative achieves its smallest possible eigenvalue only if the structure is qc-Einstein.
Differential Geometry Analysis of PDEs